Contact email: carlos.diaz@cenace.gob.mx
Summary
After editing an Excel `.xlsx` file using Telerik RadSpreadsheet and saving it via the default Save option, the saved file becomes corrupted. It no longer opens in RadSpreadsheet (throws an error) and shows a repair warning in Microsoft Excel.
Reproduction Steps
1. Upload an Excel `.xlsx` file to the `ABC` folder on the server.
2. Load the file in RadSpreadsheet via a basic viewer page.
3. Make any small edit (e.g., change a cell’s value).
4. Click the built-in Save option in the RadSpreadsheet toolbar.
5. Attempt to:
- Reopen the saved file in RadSpreadsheet → Error: Object reference not set to an instance of an object.
- Open in Excel → Warning: “We found a problem with some content in ‘filename’. Do you want us to try to recover as much as we can?”
Files Attached
- `Original.xlsx` — Before editing, opens fine in both RadSpreadsheet and Excel.
- `Modified.xlsx` — After saving via RadSpreadsheet, causes errors.
- Screenshot of:
- RadSpreadsheet error :
- Excel repair prompt
Code Snippet :
<telerik:RadSpreadsheet ID="sample" runat="server" Visible="false" style="font-size: 10px;" />
protected void Page_Load(object sender, EventArgs e)
{
string fileName = (string)Session["SelectedFileName"];
SheetLoad(fileName);
}
private void SheetLoad(string fileName)
{
try
{
string filePath = Server.MapPath("~/ABC/" + fileName);
if (!File.Exists(filePath))
{
string errorMsg = "File not found: " + filePath;
ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('File not found!');", true);
return;
}
// Load spreadsheet using Telerik document provider
sample.Provider = new SpreadsheetDocumentProvider(filePath);
sample.Visible = true;
}
catch (Exception ex)
{
string errorMsg = "Error opening file: " + ex.Message + " | File: " + fileName;
ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('Error loading file!');", true);
}
}
**Observation:**
* This only happens for **some files**, especially ones that likely contain advanced Excel features.
* Other simpler files save and reload without any issue.
**Assumption:**
It seems the default save behavior of RadSpreadsheet is **not preserving some Excel structures**, leading to file corruption on save.
Dear Telerik Support. I found another bug related to this one below.
This line of code also causes the same issue.
$find("txtYear").clear();
See attached Console debug output.
It is my opinion that a hot fix needs to be done asap! The work around that Derek posted on May 23rd falls short of the bigger issue. This is a serious matter and needs to be addressed immediately.
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Component in .ascx file:
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AllowCustomText="true"
MarkFirstMatch="true"
Skin="Bootstrap"
AutoPostBack="true"
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DataTextField="Name"
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Please advise. Thanks!
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Before 2025 Q1
In 2025 Q1
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<telerik:RadWindow ID="RadWindow1" runat="server" RenderMode="Classic" VisibleOnPageLoad="true" NavigateUrl="Default.aspx">
</telerik:RadWindow>
Hello
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To replicate this beahavior:
1. Create a new Telerik VB Webform Site
2. Add a Class Library Net Framework project to the solution.
3. Add a reference to Telerik.Web.UI to the Class Library project (optional).
4. Save and close solution.
5. Reopen it and run the Telerik Upgrade Wizard Project.
It only shows the Class Library project ...
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See attached screen shots.
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Bug report
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Reproduction of the problem
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Current behavior
Android - "There was a problem printing the page. Please try again." - no preview
Windows - the Print dialog shows and closes automatically
Expected/desired behavior
Print preview is available, allowing you to find a printer and print
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Just a heads-up - some of the demo pages are generating errors:
Server Error in '/aspnet-ajax' Application.
Runtime Error
Description: An exception occurred while processing your request. Additionally, another exception occurred while executing the custom error page for the first exception. The request has been terminated.
I have found this on: